1. Field
The described technology relates generally to a rechargeable battery with an external short-circuit part.
2. Description of the Related Art
A rechargeable battery differs from a primary battery in that it can be repeatedly charged and discharged, while the latter is not designed to be recharged.
A low-capacity rechargeable battery is used in small portable electronic devices such as mobile phones, notebook computers, and camcorders, while a high-capacity rechargeable battery can be used as a power source for driving a motor of a hybrid vehicle and the like.
A rechargeable battery includes an electrode assembly formed by disposing a positive electrode and a negative electrode at respective surfaces of a separator, a case for accommodating the electrode assembly, and a cap assembly for sealing an opening of the case, and negative and positive electrode terminals electrically connected to the electrode assembly while being provided to extend through the cap assembly.
While being repeatedly charged and discharged, the rechargeable battery may generate excessive heat inside of the case, or an electrolyte solution may be decomposed therein.
Such heat generation or electrolyte solution decomposition may increase an internal pressure of the rechargeable battery.
The increased internal pressure may cause ignition or explosion of the rechargeable battery.
Thus, in order to prevent the ignition and explosion of the rechargeable battery as a result of increased internal pressure, the case may be provided with an external short-circuit part.
When the internal pressure of the rechargeable battery increases, the external short-circuit part short-circuits the negative electrode of the electrode assembly with the positive electrode thereof outside of the rechargeable battery.
When the external short-circuit part is short-circuited and thus the battery is discharged, a charging state of the electrode assembly becomes low.
For example, the external short-circuit part includes a connection plate that is connected to the negative electrode terminal, and a membrane that is connected to the cap plate to maintain a separated state with the connection plate, and the membrane may be inversely deformed to contact the connection plate.
The cap plate and the membrane are connected to the positive electrode terminal.
The connection plate may be provided with a through-hole so as not to disturb the inverse deformation of the membrane.
The through-hole may allow foreign materials and moisture from outside to permeate through the space between the connection plate and the membrane.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that is not part of the prior art that is already known to a person of ordinary skill in the art.